{"id":"CVE-2020-27222","details":"In Eclipse Californium version 2.3.0 to 2.6.0, the certificate based (x509 and RPK) DTLS handshakes accidentally fails, because the DTLS server side sticks to a wrong internal state. That wrong internal state is set by a previous certificate based DTLS handshake failure with TLS parameter mismatch. The DTLS server side must be restarted to recover this. This allow clients to force a DoS.","modified":"2026-08-27T08:15:07.862522Z","published":"2021-02-03T16:15:13.117Z","references":[{"type":"REPORT","url":"https://bugs.eclipse.org/bugs/show_bug.cgi?id=570844"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/eclipse-californium/californium","events":[{"introduced":"ced7ef98f325b62a1d23011e0bc67b1bdd662293"},{"last_affected":"864c58f817e2d2a403c6a7bf54e75fbc5c408dbe"}],"database_specific":{"cpe":"cpe:2.3:a:eclipse:californium:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"2.3.0"},{"last_affected":"2.6.0"}],"source":"CPE_RANGE"}}],"versions":["2.6.0","2.5.0","2.4.0","2.3.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2020-27222.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"}]}